1. Field of the Invention
The present invention is generally related to an engine drain system and, more particularly, to an engine drain system that allows complete draining of an internal combustion engine from a single point which is connected directly to a manifold that is mounted below the lowest portion of a water cooling system of the internal combustion engine.
2. Description of the Prior Art
Many different types of internal combustion engines are well known to those skilled in the art. In certain applications, such as in marine propulsion systems, internal combustion engines draw cooling water from a body of water in which a watercraft is operated. When the engine is inoperative, a certain quantity of water collects, or pools, within locations of the engine and does not easily drain out of the engine. When the operator of the watercraft wants to drain the cooling water from the engine, the process can be difficult and time consuming. Part of the reason for the difficulty in draining a marine engine is that it is usually necessary to drain the engine from several different locations to assure that all the entrapped water within the engine is removed. If this is not done carefully and completely, the remaining water within the engine block can freeze and cause serious damage to the engine and its related components.
U.S. Pat. No. 5,441,431, which issued to Brogdon on Aug. 15, 1995, describes a fresh water flushing system for a marine engine in a boat. The flushing system can be used whether the boat is in or out of the water. The system comprises a control panel mounted on the interior of the boat, a plurality of tubular T-shaped interconnection fittings in a raw sea water cooling conduit, and a fresh water flush valve. The components are connected for fresh water fluid flow. The fresh water flush valve has a valve plunger for establishing a fresh water flow between the control panel and the T-shaped interconnection fittings.
U.S. Pat. No. 5,393,252, which issued to Brogdon on Feb. 28, 1995, discloses a fresh water flushing system for use in a boat. The system comprises a control panel mounted in the proximity of the marine engine and a fresh water flush valve. Hoses are connected to the fresh water flush valve and also to various components of the marine engine system to provide fresh water fluid flow within the engine. Alternative embodiments are included for marine vessels with more than one engine.
U.S. Pat. No. 5,362,266, which issued to Brogdon on Nov. 8, 1994, describes a flush master fresh water flushing system. The components of the system are connected for fresh water fluid flow with a plurality of standard radiator hoses. The fresh water flush valve has a valve plunger for establishing fresh water flow between the control panel and "T" shaped interconnection fittings. Further, the fresh water flush valve has a plurality of axial outlet ports to proportionally direct the flow of fresh water to the appropriate "T" shaped interconnection fitting in the raw sea water cooling conduit of the marine engine. A valve plug is provided to secure a positive closure when the fresh water flow is disconnected. The valve plug has a tapered body and a "O" ring to affect a positive seal and insure that no fluid backflow occurs when the flushing system is not in use and operation of the marine engine is operating under normal conditions in the sea water. All of the fixed and movable parts are fabricated from material that resists salt air and salt water corrosion.
U.S. Pat. No. 5,067,448, which issued to Nakase et al on Nov. 26, 1991, describes an exhaust cooling device for a small sized boat engine. A small watercraft embodies an improved exhaust system that is substantially completely watercooled by a cooling jacket. The exhaust system includes an elastic joint that is also completely surrounded by the cooling jacket so as to insure adequate cooling under all running conditions. A damming arrangement is incorporated so as to insure that all of the exhaust portions being cooled will be completely encircled with cooling water even when low amounts of water are being circulated and a drain system is also provided to as to insure that the cooling jackets will be drained when the watercraft is removed from a body of water.
U.S. Pat. No. 4,699,598, which issued to Bland et al on Oct. 13, 1987, describes a marine propulsion device with a water supply system. The device comprises an internal combustion engine, a propulsion unit adapted to be pivotally mounted on the transom of a boat for pivotal movement relative to the transom about a generally vertical steering axis, and about a generally horizontal tilt axis, the propulsion unit including a propeller operably connected to the engine. The device also comprises a pump for pumping water from the exterior of the propulsion unit to the engine, and a conduit extending from the pump to the engine and having a low point below both the pump and the connection of the conduit to the engine. It also comprises a drain for draining water from adjacent the low point of the conduit.
U.S. Pat. No. 4,693,690, which issued to Henderson on Sep. 15, 1987, describes a quick drain assembly for a boat engine. The device is used for an inboard boat engine, especially an engine of the type having a water jacket to which a plurality of drain cocks are connected through which engine coolant must be drained after each use of the engine. The quick drain device is in the form of a barrel having a plurality of lateral tubes radiating therefrom. An expandable stopper is received within the barrel and covers the ends of the tube and thereby prevents flow therethrough. The other ends of the lateral tubes are connected to the drain cocks or drain plugs located on the engine block. Removal of the expandable stopper simultaneously drains all of the drain plugs.
U.S. Pat. No. 5,329,888, which issued to Luckett et al on Jul. 19, 1994, discloses a thermostat housing assembly for a marine engine. The housing assembly has a first inlet to receive sea water and an outlet that is connected to the circulating pump that circulates cooling water to the engine. A baffle is located in the housing and prevents direct flow between the sea water inlet and the outlet. The housing defines a pair of passages with a first of the passages providing communication between the sea water inlet and forms a first chamber which communicates with a pair of manifold outlets that are connected to the manifold. A second of the passages provides communication between the sea water inlet and the outlet to the recirculation pump. The housing also includes a return inlet for returning water from the engine and the return inlet is connected to the second passages. A thermostat is mounted in an opening between the passages and when the thermostat is open a portion of the returning cooling water will be directed through the thermostat opening to the first passage and mixed with incoming sea water and then directed to the manifolds.
The patents described above are hereby explicitly incorporated by reference in the description of the preferred embodiment of the present invention.
It would be significantly beneficial if a system could be developed in which a marine propulsion engine can be quickly and easily drained to remove all of the water from the internal chambers of the engine's cooling and exhaust system. It would also be significantly beneficial if a system of this type could be provided in which no water is left remaining within any of the cooling system chambers after completion of the draining operation.